Subnet Calculator
0
32
64
96
128
160
192
224
Network
Host
Broadcast
Public IP Information
IP Address Information
64.129.4.64
01000000100000010000010001000000
255.255.255.192
11111111111111111111111111000000
64.129.4.64
01000000100000010000010001000000
64.129.4.127
01000000100000010000010001111111
0.0.0.63
00000000000000000000000000111111
/26
Network Bits: 26 |Host Bits: 6
64.129.4.65
01000000100000010000010001000001
64.129.4.126
01000000100000010000010001111110
Network Information
64
62
64.129.4.65 – 64.129.4.126
Subnet Cheat Sheet
| CIDR | Subnet Mask | Wildcard Mask | Total IPs | Usable Hosts | Network Bits | Host Bits |
|---|---|---|---|---|---|---|
| /32 | 255.255.255.255 | 0.0.0.0 | 1 | 1 | 32 | 0 |
| /31 | 255.255.255.254 | 0.0.0.1 | 2 | 2 | 31 | 1 |
| /30 | 255.255.255.252 | 0.0.0.3 | 4 | 2 | 30 | 2 |
| /29 | 255.255.255.248 | 0.0.0.7 | 8 | 6 | 29 | 3 |
| /28 | 255.255.255.240 | 0.0.0.15 | 16 | 14 | 28 | 4 |
| /27 | 255.255.255.224 | 0.0.0.31 | 32 | 30 | 27 | 5 |
| /26 | 255.255.255.192 | 0.0.0.63 | 64 | 62 | 26 | 6 |
| /25 | 255.255.255.128 | 0.0.0.127 | 128 | 126 | 25 | 7 |
| /24 | 255.255.255.0 | 0.0.0.255 | 256 | 254 | 24 | 8 |
| /23 | 255.255.254.0 | 0.0.1.255 | 512 | 510 | 23 | 9 |
| /22 | 255.255.252.0 | 0.0.3.255 | 1,024 | 1,022 | 22 | 10 |
| /21 | 255.255.248.0 | 0.0.7.255 | 2,048 | 2,046 | 21 | 11 |
| /20 | 255.255.240.0 | 0.0.15.255 | 4,096 | 4,094 | 20 | 12 |
| /19 | 255.255.224.0 | 0.0.31.255 | 8,192 | 8,190 | 19 | 13 |
| /18 | 255.255.192.0 | 0.0.63.255 | 16,384 | 16,382 | 18 | 14 |
| /17 | 255.255.128.0 | 0.0.127.255 | 32,768 | 32,766 | 17 | 15 |
| /16 | 255.255.0.0 | 0.0.255.255 | 65,536 | 65,534 | 16 | 16 |
| /15 | 255.254.0.0 | 0.1.255.255 | 131,072 | 131,070 | 15 | 17 |
| /14 | 255.252.0.0 | 0.3.255.255 | 262,144 | 262,142 | 14 | 18 |
| /13 | 255.248.0.0 | 0.7.255.255 | 524,288 | 524,286 | 13 | 19 |
| /12 | 255.240.0.0 | 0.15.255.255 | 1,048,576 | 1,048,574 | 12 | 20 |
| /11 | 255.224.0.0 | 0.31.255.255 | 2,097,152 | 2,097,150 | 11 | 21 |
| /10 | 255.192.0.0 | 0.63.255.255 | 4,194,304 | 4,194,302 | 10 | 22 |
| /9 | 255.128.0.0 | 0.127.255.255 | 8,388,608 | 8,388,606 | 9 | 23 |
| /8 | 255.0.0.0 | 0.255.255.255 | 16,777,216 | 16,777,214 | 8 | 24 |
| /7 | 254.0.0.0 | 1.255.255.255 | 33,554,432 | 33,554,430 | 7 | 25 |
| /6 | 252.0.0.0 | 3.255.255.255 | 67,108,864 | 67,108,862 | 6 | 26 |
| /5 | 248.0.0.0 | 7.255.255.255 | 134,217,728 | 134,217,726 | 5 | 27 |
| /4 | 240.0.0.0 | 15.255.255.255 | 268,435,456 | 268,435,454 | 4 | 28 |
| /3 | 224.0.0.0 | 31.255.255.255 | 536,870,912 | 536,870,910 | 3 | 29 |
| /2 | 192.0.0.0 | 63.255.255.255 | 1,073,741,824 | 1,073,741,822 | 2 | 30 |
| /1 | 128.0.0.0 | 127.255.255.255 | 2,147,483,648 | 2,147,483,646 | 1 | 31 |
| /0 | 0.0.0.0 | 255.255.255.255 | 4,294,967,296 | 4,294,967,294 | 0 | 32 |
Quick Reference
Frequently Asked Questions
How to Use
Enter an IP address and CIDR prefix above to calculate subnet details including network address, broadcast address, subnet mask, and usable host range.
CIDR Notation
CIDR (Classless Inter-Domain Routing) replaced traditional classful networking. The prefix length (e.g., /24) specifies how many bits identify the network, with the remaining bits identifying hosts.
Common Subnet Sizes
/24 (254 hosts) is the most common LAN size. /16 (65,534 hosts) suits large campuses. /30 (2 hosts) is used for point-to-point links. /32 represents a single host.